Shear Properties And Finite Element Analysis Of Reinforced Concrete Beams With High-strength Stirrups

The intensity of the High strength reinforced bar is high, and the property of it is stable. It can reduce the building's deadweight effectively, raise the availability of resources, and become popular in overseas. After the application of the Code for Design of Concrete Structures (GB50010-2002), high strength reinforced bars (HRB400) have been widely used in concrete structures as the shear stirrup. But our country is short of the relative research about the high strength reinforced bar as the shear stirrup. The formula depending on the statistical analysis of the test datum may not satisfy the actual requirement. Therefore the test datum about the high-strength concrete beam stirrups should be collected to improve the formula on calculating the ultimate shear capacity.In this paper, 335 non-web reinforcement beams and 104 high-strength stirrups web reinforcement beams were collected to test datum. The factors that affect shear strength of concrete including shear span ratio, concrete strength, ratio of longitude bar, ratio of stirrup, overall thickness of member and so on were analyzed and Summarized.The revised angle truss-arch model was proposed based on the relative literature and experimental data collected. The soft phenomenon of concrete, arch-effects and others were considered in the model. A revised formula on calculating the ultimate shear capacity of RC beam under the concentrated load was proposed based on the test data collected and the truss-arch model. The results from the proposed formula conformed fine to the experiment data. So it could be used to predict the ultimate shear capacity.On the basis of statistical data, an empirical equation to estimate the ultimate shear capacity was proposed. In order to prove the universality of the formula, the calculation of the formula was compared with the test results, Code for design of Concrete structures (GB50010-2002) and ACI 318M-05 Building Code. The results indicated that the calculation of Chinese code was high and insecurity, the calculation of American code was low and conservative while the calculation of regression formula lay between the two. It can be used to calculate the shear capacity of the high-strength concrete beam stirrups.The high-strength concrete beam stirrups listed in literature were analyzed by ANSYS. The results of nonlinear element analysis were compared with the test results. It indicated that the analysis was in good agreement with the test results.